A dose-related positive effect of inhaled simvastatin loaded PLGA nanoparticles on paraquat-induced pulmonary fibrosis in rats

Development, Optimization, and in vitro Evaluation of Silybin-loaded PLGA Nanoparticles and Decoration with 5TR1 Aptamer for Targeted Delivery to Colorectal Cancer Cells

Chemotherapeutic agents often lack specificity, intratumoral accumulation, and face drug resistance. Targeted drug delivery systems based on nanoparticles (NPs) mitigate these issues. Poly (lactic-co-glycolic acid) (PLGA) is a well-studied polymer, commonly modified with aptamers (Apts) for cancer diagnosis and therapy. In this study, silybin (SBN), a natural agent with established anticancer properties, was encapsulated into PLGA NPs to control delivery and improve its poor solubility. The field-emission scanning electron microscopy (FE-SEM) showed spherical and uniform morphology of optimum SBN-PLGA NPs with 138.57±1.30nm diameter, 0.202±0.004 polydispersity index (PDI), -16.93±0.45mV zeta potential (ZP), and 70.19±1.63% entrapment efficiency (EE). The results of attenuated total reflectance-Fourier transform infrared (ATR-FTIR) showed no chemical interaction between formulation components, and differential scanning calorimetry (DSC) thermograms confirmed efficient SBN entrapment in the carrier. Then, the optimum formulation was functionalized with 5TR1 Apt for active targeted delivery of SBN to colorectal cancer (CRC) cells in vitro. The SBN-PLGA-5TR1 nanocomplex released SBN at a sustained and constant rate (zero-order kinetic), favoring passive delivery to acidic CRC environments. The MTT assay demonstrated the highest cytotoxicity of the SBN-PLGA-5TR1 nanocomplex in C26 and HT29 cells and no significant cytotoxicity in normal cells. Apoptosis analysis supported these results, showing early apoptosis induction with SBN-PLGA-5TR1 nanocomplex which indicated this agent could cause programmed death more than necrosis. This study presents the first targeted delivery of SBN to cancer cells using Apts. The SBN-PLGA-5TR1 nanocomplex effectively targeted and suppressed CRC cell proliferation, providing valuable insights into CRC treatment without harmful effects on healthy tissues.

Emerging delivery approaches for targeted pulmonary fibrosis treatment

Pulmonary fibrosis (PF) is a progressive, and life-threatening interstitial lung disease which causes scarring in the lung parenchyma and thereby affects architecture and functioning of lung. It is an irreversible damage to lung functioning which is related to epithelial cell injury, immense accumulation of immune cells and inflammatory cytokines, and irregular recruitment of extracellular matrix. The inflammatory cytokines trigger the differentiation of fibroblasts into activated fibroblasts, also known as myofibroblasts, which further increase the production and deposition of collagen at the injury sites in the lung. Despite the significant morbidity and mortality associated with PF, there is no available treatment that efficiently and effectively treats the disease by reversing their underlying pathologies. In recent years, many therapeutic regimens, for instance, rho kinase inhibitors, Smad signaling pathway inhibitors, p38, BCL-xL/ BCL-2 and JNK pathway inhibitors, have been found to be potent and effective in treating PF, in preclinical stages. However, due to non-selectivity and non-specificity, the therapeutic molecules also result in toxicity mediated severe side effects. Hence, this review demonstrates recent advances on PF pathology, mechanism and targets related to PF, development of various drug delivery systems based on small molecules, RNAs, oligonucleotides, peptides, antibodies, exosomes, and stem cells for the treatment of PF and the progress of various therapeutic treatments in clinical trials to advance PF treatment.

Molecular mechanism of paraquat-induced ferroptosis leading to pulmonary fibrosis mediated by Keap1/Nrf2 signaling pathway

Paraquat (PQ) is a widely used and highly toxic pesticide that is often actively ingested and causes pulmonary fibrosis in patients. Ferroptosis is a regulated form of non-apoptotic cell death associated with iron-dependent lipid peroxidation. Previous studies have shown that ferroptosis is involved in the occurrence and development of acute lung injury (ALI). In this study, a model rat with inflammatory response, oxidative stress, lipid peroxidation, and pulmonary fibrosis was successfully established by PQ administration. The occurrence of ferroptosis in PQ model rats was confirmed by TUNEL staining, iron ion detection, and Ferroptosis related biomarkers detection. Western blotting (WB) and real-time PCR (RT-PCR) showed that the expression of Keap1 was significantly up-regulated and the expression of Nrf2 was significantly down-regulated in the lung tissue of PQ rats. Further transcriptomics and proteomics confirmed: (1) Enrichment of molecular processes related to iron ion binding; (2) Keap1 may promote Nrf2 ubiquitination and lead to Nrf2 degradation; (3) There is functional enrichment in ferroptosis related pathways. Our results suggest that PQ can regulate Keap1/Nrf2 signaling pathway, leading to increased lipid peroxidation and abnormal iron uptake, thereby inducing iron death and exacerbating the progression of pulmonary fibrosis. Our study provides new insights into PQ-induced pulmonary fibrosis.

An overview on nanoplatforms for statins delivery: Perspectives for safe and effective therapy

Statins are the most widely used pharmacological agents for reducing blood cholesterol levels and treating atherosclerotic cardiovascular diseases. Most of the statins' derivatives have been limited by water solubility, bioavailability, and oral absorption, which has led to adverse effects on several organs, especially at high doses. As an approach to reducing statin intolerance, achieving a stable formulation with improved efficacy and bioavailability at low doses has been suggested. Nanotechnology-based formulations may provide a therapeutic benefit over traditional formulations in terms of potency and biosafety. Nanocarriers can provide tailored delivery platforms for statins, thereby enhancing the localized biological effects and lowering the risk of undesired side effects while boosting statin's therapeutic index. Furthermore, tailored nanoparticles can deliver the active cargo to the desired site, which culminates in reducing off-targeting and toxicity. Nanomedicine could also provide opportunities for therapeutic methods by personalized medicine. This review delves into the existing data on the potential improvement of statin therapy using nano-formulations.